1655443640 has 64 divisors (see below), whose sum is σ = 3851604000. Its totient is φ = 639871488.

The previous prime is 1655443619. The next prime is 1655443649. The reversal of 1655443640 is 463445561.

It is a junction number, because it is equal to n+sod(n) for n = 1655443594 and 1655443603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1655443649) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 216767 + ... + 224273.

Almost surely, 2^1655443640 is an apocalyptic number.

1655443640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1655443640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1925802000).

1655443640 is an abundant number, since it is smaller than the sum of its proper divisors (2196160360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1655443640 is a wasteful number, since it uses less digits than its factorization.

1655443640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7704 (or 7700 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 38.

The square root of 1655443640 is about 40687.1434239368. The cubic root of 1655443640 is about 1182.9638316456.

The spelling of 1655443640 in words is "one billion, six hundred fifty-five million, four hundred forty-three thousand, six hundred forty".